Liquid lithium divertor analysis using coupled plasma material interaction model

Journal Article · 19 November 2024 · Nuclear Materials and Energy

DOI: https://doi.org/10.1016/j.nme.2024.101821 · OSTI ID:2478177

Khodak, Andrei ^[1]; Emdee, Eric ^[1]; Goldston, Robert ^[1]; Maingi, Rajesh ^[1]

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1. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

A liquid lithium divertor can improve performance of future fusion devices by creating efficient power exhaust and improving the energy confinement via pumping of the hydrogen isotopes. In addition, significantly higher heat fluxes can be handled if controlled vapor shielding is used to redistribute the divertor heat flux over a wider area. Design and optimization of such a system calls for an analysis model which includes a strong two-way coupling between the plasma and divertor material. The incoming plasma heat and particle flux will affect the divertor surface temperature, which is a defining factor of the lithium evaporative and sputtered flux going into the plasma. Results of the coupled model based on the plasma edge code SOLPS-ITER and the computational fluid dynamics (CFD) code ANSYS-CFX will be presented for different configurations. An analytical slab flow model is used as a heat transfer boundary condition for SOLPS, defining particle flux from the wall via calculation of the surface temperature. At the final step, results of the SOLPS analysis are verified using a 3D CFD magnetohydrodynamics (MHD) analysis which uses heat and particle flux from SOLPS as a boundary condition. In addition to plasma heat flux, both analytical and CFD temperature models include several plasma material interaction effects, such as lithium evaporation, condensation and sputtering based on deuterium target flux. New adatom sputtering model based on the available experimental data is presented. Analytical model is expanded to include free surface axisymmetric configurations. Results of parametric studies of the divertor configurations with different lithium inlet temperature and velocity will be presented leading to the optimal design resulting in the lowest possible lithium contamination in the core.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES)
• Grant/Contract Number: AC02-09CH11466
• OSTI ID: 2478177
• Journal Information: Nuclear Materials and Energy, Journal Name: Nuclear Materials and Energy Vol. 41; ISSN 2352-1791
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English